Terfezia boudieri and Terfezia claveryi inhibit the LPS/IFN-γ-mediated inflammation in RAW 264.7 macrophages through an Nrf2-independent mechanism.

Desert truffles have been used as traditional treatments for numerous inflammatory disorders. However, the molecular mechanisms underlying their anti-inflammatory effects in RAW 264.7 macrophages have yet to be fully elucidated. The present study investigated the anti-inflammatory activities of two main desert truffles, Terfezia boudieri and T. claveryi, and the underlying mechanisms associated with their anti-inflammatory activities in RAW 264.7 macrophages stimulated with lipopolysaccharide/interferon-gamma (LPS/IFN-γ). Our results demonstrated that treatment with T. boudieri and T. claveryi extracts effectively suppressed the inflammatory response in LPS/IFN-γ-stimulated RAW 264.7 macrophages. Specifically, T. boudieri extract was found to reduce the production of nitric oxide and inhibit the expression of various pro-inflammatory markers, including inducible nitric oxide synthase, cyclooxygenase-2 (COX-2), tumor necrosis factor-α, and interleukin-6 (IL-6) at both the mRNA and protein levels. Similarly, T. claveryi extract exhibited comparable inhibitory effects, except for the expression of IL-6 and COX-2 at the protein level, where no significant effect was observed. Moreover, both studied extracts significantly downregulated the microRNA expression levels of miR-21, miR-146a, and miR-155, suggesting that T. boudieri and T. claveryi suppress the inflammatory response in LPS/IFN-γ-stimulated RAW 264.7 cells through an epigenetic mechanism. Furthermore, our study reveals a new mechanism for the anti-inflammatory properties of desert truffle extracts. We show for the first time that Terfezia extracts do not rely on the nuclear factor erythroid 2-related factor 2 pathway, previously linked to anti-inflammatory responses. This expands our understanding of natural product anti-inflammatory mechanisms and could have important implications for developing new therapies. To account for differences in truffle effects, extracts prepared were subjected to secondary metabolites profiling using UPLC-MS. UPLC-MS led to the annotation of 87 secondary metabolites belonging to various classes, including amino acids, carbohydrates, alkaloids, amides, fatty acids, sterols, and phenolic compounds. Therefore, these results indicate that T. boudieri and T. claveryi exhibit anti-inflammatory activities through suppressing multiple inflammatory mediators and cytokines and may be potential anti-inflammatory agents.

Dawood AS ，Sedeek MS ，Farag MA ，Abdelnaser A ... -  《Scientific Reports》

Ethyl acetate fraction from Nymphaea hybrida Peck modulates inflammatory responses in LPS-stimulated RAW 264.7 cells and acute inflammation murine models.

Nymphaea hybrida Peck is used as a traditional medicinal herb for treating pain and inflammatory diseases, and known for its ornamental value and as a hot drink. However, the effects of N. hybrida polar fractions on lipopolysaccharide (LPS)-induced in vitro inflammation model and acute inflammation murine models have yet to be evaluated. The aim of this study was to elucidate the anti-inflammatory effects of N. hybrida ethanol extract (NHE) and its polar fractions: petroleum ether (PE), methylene chloride (MC), ethyl acetate (EA), methanol (ME), and water (WA). The underlying molecular mechanisms of active fraction in LPS-stimulated RAW 264.7 murine macrophages were further investigated. Fractions with potential anti-inflammatory effects were screened using direct nitric oxide (NO) radical scavenging and cyclooxygenase (COX)-2 inhibition assays in vitro. The anti-inflammatory properties of potential fraction were evaluated in LPS-stimulated RAW264.7 cells, xylene-induced ear edema, carrageenan-induced paw edema and xylene-induced Evans blue exudation of acute inflammation murine models. The regulation of nuclear factor-κB (NF-κB) and mitogen-activated protein kinase (MAPK) signaling pathways were investigated using western blotting and immunofluorescence. Compared to other polar fractions, NHE-EA displayed higher phenol and flavonoid content, and exerted greater activity in direct NO radical scavenging and COX-2 inhibition assay in vitro. NHE-EA markedly decreased the levels of inflammatory mediators, NO and prostaglandin E2 (PGE2), by suppressing the over-expression of inducible nitric oxide synthase (iNOS) and COX-2 in LPS-stimulated RAW264.7 cells. The NHE-EA fraction dose-dependently alleviated over-elevation of LPS-associated intracellular calcium and decreased the abnormal secretion of pro-inflammatory cytokines, tumor necrosis factor-α (TNF-α), interleukin-1β (IL-1β), IL-6, and interferon-γ (IFN-γ). The combination with NHE-EA effectively attenuated the activation and nuclear translocation of NF-κB p65, and the phosphorylation of extracellular signal-regulated kinases (ERK), c-Jun N-terminal kinases (JNK), and p38 kinases of MAPK pathways. NHE-EA could significantly ameliorate the degree of swelling of the mice ear and paw, the skin exudation of Evans blue and the excessive secretion of inflammatory cytokines. Our results demonstrated that NHE-EA was the most active polar fraction of N. hybrida extracts. It inhibited the LPS-associated inflammatory response by blocking the activation of NF-κB and MAPKs pathways in RAW264.7 cells. It also effectively alleviated the inflammatory response of acute inflammation. These results indicated the role of NHE-EA as adjuvants and their potential role in alternative strategy for the treatment of inflammatory diseases.

Zhang Z ，Jiang S ，Tian H ，Zeng Y ，He K ，Lin L ，Yu F ... -  《-》

Inhibitory Effects of Aucklandia lappa Decne. Extract on Inflammatory and Oxidative Responses in LPS-Treated Macrophages.

Lim JS ，Lee SH ，Lee SR ，Lim HJ ，Roh YS ，Won EJ ，Cho N ，Chun C ，Cho YC ... -  《MOLECULES》

Anti-inflammatory and antioxidant activities of methanol extract of Piper betle Linn. (Piper betle L.) leaves and stems by inhibiting NF-κB/MAPK/Nrf2 signaling pathways in RAW 264.7 macrophages.

Oxidative stress and chronic inflammation are closely linked to various diseases. However, previous studies have demonstrated that plant extracts could prevent and alleviate these adverse outcomes. Piper betle Linn. (Piper betle L.) is a cosmopolitan plant that belongs to the Piperaceae family, whose leaves are edible and possess several health benefits. This study sought to characterize the anti-inflammatory and antioxidant effects of a methanol extract of Piper betle L. leaves and stems (MPBLLS). MPBLLS was found to have a dose-dependent radical scavenging effect, as demonstrated by the 2,2-diphenyl-1-picrylhydrazyl assay. Additionally, MPBLLS inhibited the lipopolysaccharide (LPS)-stimulated production of nitric oxide and prostaglandin E2 by reducing the expression of inducible nitric oxide synthase and cyclooxygenase-2 in RAW 264.7 macrophages without affecting cell viability. Furthermore, our findings suggested that the inhibitory effects of MPBLLS on pro-inflammatory cytokines such as tumor necrosis factor-α, interleukin-1β, and interleukin-6 were due to the inhibition of the nuclear factor-κB (NF-κB) and mitogen-activated protein kinase (MAPK) signaling pathways in LPS-treated RAW 264.7 macrophages. MPBLLS and hydroxychavicol, a major constituent of MPBLLS, suppressed LPS-induced translocation of NF-κB p65 from cytoplasm to nucleus. Interestingly, MPBLLS increased nuclear factor erythroid 2-related factor 2 (Nrf2) protein levels and transcription levels of Nrf2 target genes in a dose-dependent manner. Collectively, our findings suggest that MPBLLS could serve as a basis for the development of novel orally-administered therapies due to its inhibitory effects on oxidative and inflammatory stress. DATA AVAILABILITY: The data presented in this study are available on request from the corresponding author.

Seo J ，Lee U ，Seo S ，Wibowo AE ，Pongtuluran OB ，Lee K ，Han SB ，Cho S ... -  《-》

Regulation of anti-inflammatory and antioxidant responses by methanol extract of Mikania cordata (Burm. f.) B. L. Rob. leaves via the inactivation of NF-κB and MAPK signaling pathways and activation of Nrf2 in LPS-induced RAW 264.7 macrophages.

Mikania cordata (Burm. f.) B.L. Rob. has been traditionally used in tropical countries throughout Asia and Africa to treat gastric ulcers, dyspepsia, and dysentery. However, the mechanisms responsible for its anti-inflammatory and antioxidant activities are not fully understood. Therefore, this study sought to investigate the anti-inflammatory and antioxidant effects of methanol extracts of M. cordata (MMC) on inflammation and oxidative stress in lipopolysaccharide (LPS)-stimulated murine RAW 264.7 macrophages and elucidate its underlying regulatory mechanism. MMC significantly suppressed the production of nitric oxide (NO) and prostaglandin E2 (PGE2) in LPS-stimulated RAW 264.7 macrophages by downregulating the expression of inducible NO synthase (iNOS) and cyclooxygenase-2 (COX-2) at both the mRNA and protein levels. Moreover, MMC effectively reduced the mRNA expression levels and production of pro-inflammatory cytokines, including interleukin-6 (IL-6), IL-1β, and tumor necrosis factor-α (TNF-α). These suppressive effects of MMC on pro-inflammatory mediators and cytokines were mediated through the inhibition of transforming growth factor beta-activated kinase 1 (TAK1), which subsequently blocked the activation of nuclear factor-κB (NF-κB) and mitogen-activated protein kinases (MAPKs). MMC also upregulated the nuclear factor erythroid-2-related factor 2 (Nrf2) by inducing the degradation of Kelch-like ECH-related protein 1 (Keap1), an Nrf2-specific E3 ligase. Accordingly, MMC enhanced Nrf2 target gene expression of anti-oxidative regulators such as heme oxygenase-1 (HO-1) and NAD(P)H quinone oxidoreductase 1 (NQO1). However, it had minimal effect on the DPPH radical scavenging capacity in vitro. Collectively, these findings demonstrate that MMC holds promise as a potential therapeutic agent for alleviating inflammation-related diseases and oxidative stress.

Kang E ，Lee J ，Seo S ，Uddin S ，Lee S ，Han SB ，Cho S ... -  《-》